package com.routing;

import com.rabbitmq.client.*;

/**
 * 案例是依据消息的严重程度来分发到不同的队列的，对应官方的Routing案例
 * 需要启动不同的ReceiveLogsDirect实例来创建出多个消费者以及多个临时队列出来
 */
public class ReceiveLogsDirect {

    private static final String EXCHANGE_NAME = "direct_logs";


    //java -cp $CP ReceiveLogsDirect warning error > logs_from_rabbit.log
    //java -cp $CP ReceiveLogsDirect info warning error
    public static void main(String[] argv) throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection connection = factory.newConnection();
        Channel channel = connection.createChannel();

        channel.exchangeDeclare(EXCHANGE_NAME, BuiltinExchangeType.DIRECT);
        String queueName = channel.queueDeclare().getQueue();

        if (argv.length < 1) {
            System.err.println("Usage: ReceiveLogsDirect [info] [warning] [error]");
            System.exit(1);
        }

        //依据参数创建不同的绑定
        for (String severity : argv) {
            channel.queueBind(queueName, EXCHANGE_NAME, severity);
        }
        System.out.println(" [*] Waiting for messages. To exit press CTRL+C");

        DeliverCallback deliverCallback = (consumerTag, delivery) -> {
            String message = new String(delivery.getBody(), "UTF-8");
            System.out.println(" [x] Received '" + delivery.getEnvelope().getRoutingKey() + "':'" + message + "'");
        };
        channel.basicConsume(queueName, true, deliverCallback, consumerTag -> {
        });
    }
}